This Phase I/II study evaluated the safety, tolerance, pharmacokinetics and antiviral activity of the anti-HIV antisense oligonucleotide GEM 91 administered by continuous intravenous infusion for up to 14 days. We enrolled and administered study drug to 9 HIV-infected subjects as part of this protocol. The drug infusion produced transient elevation of hepatic transaminases in a few subjects, transient mild thrombocytopenia in some, and sterile superficial thrombophlebitis in one subject. No significant reduction in HIV plasma RNA was seen with this study treatment.